<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>质数练习</title>

    <script type="text/javascript">

        var num = prompt("请输入一个大于1的整数：");

        if (num <= 1){
            alert("该值不合法！");
        }else{
            var flag = true ;
            for(var i=2;i<num;i++){

                if(num % i ==0){
                    flag = false;
                }
            }

            if(flag){
                alert(num+"是质数!");
            }else{
                alert("这个不是质数！");
            }
        }

    </script>

</head>

<body>
</body>

</html>